Traditional materials for luminescent substrates include fluorescent powder, nanocrystals, glasses, etc. In comparison to the fluorescent powder and nanocrystals, the glasses are transparent and hard, and have good chemical stability and good optical properties, and can be readily machined into a variety of products with different dimensions and shapes, for example, monitors or lighting sources with various dimensions and shapes.
For example, in vacuum microelectronics field, field emission displays typically utilize the luminescent glasses as luminescent units thereof, and are widely applied in light and display fields and attract extensive attentions from research organizations at home and abroad. The operating principle of the field emission displays is described as follows: a positive voltage is applied by an anode facing toward field emission cathode arrays (hereinafter referred to as FEAs) to form an accelerating field in vacuum condition, electrons emitted from cathodes are accelerated to impact luminescent materials on the anode and excited the luminescent materials to illuminate. The field emission displays have broad operating temperatures (−40° C.-80° C.), short response time (<1 ms), compact structure, low power consumption, and satisfy a demand for green environmental protection. The materials such as phosphor powder, luminescent glasses and luminescent films can be used as the luminescent materials in the field emission displays. However, these materials have a natural shortage of low luminescence efficiency, which significantly constrains application of the field emission displays, particularly in lighting field.